What is the CVSS score of EUVD-2026-26144?

EUVD-2026-26144 has a CVSS 3.1 base score of 7.7 (High). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N. EPSS exploitation probability: 0.0%.

Which versions of Outline are affected by EUVD-2026-26144?

Outline (getoutline) versions 0.86.0 through 1.6.x contain an authorization bypass allowing authenticated users to access and read documents from any workspace on the platform via an IDOR flaw in the…. A patch is available.

How to fix or mitigate EUVD-2026-26144?

Within 24 hours, inventory all Outline deployments and identify instances running versions 0.86.0 through 1.6.x; if affected versions are found, restrict shares.create API access and review audit logs for suspicious share creation patterns. Within 7 days, coordinate with Outline to obtain the patched version, validate the patch in a staging environment to confirm cross-workspace access controls are restored, and develop a deployment plan. Within 30 days, deploy the patched version across all production Outline instances and perform functional testing to verify that users cannot create public shares for documents outside their authorized workspace.

Outline EUVD-2026-26144

| CVE-2026-41649 HIGH

Authorization Bypass Through User-Controlled Key (CWE-639)

2026-04-28 security-advisories@github.com

Authentication Bypass Outline

7.7

CVSS 3.1 · Vendor: github

Severity by source

Vendor (github) PRIMARY

7.7 HIGH

AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N

vuln.today AI

7.7 HIGH

Authenticated low-priv API abuse (PR:L, AC:L) over the network; cross-workspace boundary crossing gives S:C, and full document disclosure gives C:H with no integrity or availability impact.

3.1 AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N

4.0 AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N

Primary rating from Vendor (github).

CVSS VectorVendor: github

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Changed

Confidentiality

High

Integrity

None

Availability

None

Lifecycle Timeline

Source Code Evidence Fetched

Jul 24, 2026 - 04:10 vuln.today

Analysis Generated

Jul 24, 2026 - 04:10 vuln.today

Patch released

May 01, 2026 - 15:54 nvd

Patch available

Apr 28, 2026 - 23:17 EUVD

EUVD ID Assigned

Apr 28, 2026 - 22:22 euvd

EUVD-2026-26144

CVE Published

Apr 28, 2026 - 22:16 nvd

HIGH 7.7

DescriptionCVE.org

Outline is a service that allows for collaborative documentation. The shares.create API endpoint starting in version 0.86.0 and prior to version 1.7.0 has an insecure direct object reference.. When both collectionId and documentId are provided in the request, the authorization logic only checks access to the collection, completely ignoring the document. This allows an authenticated attacker to generate a valid public share link for any document on the platform, including documents belonging to other workspaces. The full document contents can then be retrieved via the documents.info endpoint. Version 1.7.0 contains a patch.

AnalysisAI

Cross-workspace document disclosure in Outline (getoutline) versions 0.86.0 through 1.6.x lets an authenticated user mint a public share link for any document on the platform, then read its full contents. The flaw is an insecure direct object reference (IDOR) in the shares.create API: when a request supplies both collectionId and documentId, authorization validates only the collection and never checks that the caller may access the named document, so it works even against documents in other workspaces. A proof-of-concept is referenced by the GitHub advisory (SSVC 'poc'), but EPSS is very low (0.03%, 7th percentile) and it is not in CISA KEV, so this is publicly demonstrated but not confirmed as actively exploited.

Technical ContextAI

Outline is a self-hosted/SaaS collaborative wiki and knowledge base (cpe:2.3:a:getoutline:outline). The vulnerability lives in the shares.create endpoint of its JSON API, which produces public share links for documents. The root cause maps to CWE-639 (Authorization Bypass Through User-Controlled Key): the endpoint accepts client-supplied collectionId and documentId parameters and, when both are present, gates the operation on collection membership alone. Because the documentId is a user-controlled reference that is never independently authorized, an attacker can substitute the identifier of any document - including one in a different tenant/workspace - while passing a collection they legitimately control. Once a share link exists, the separate documents.info endpoint returns the target's full body, completing the disclosure.

RemediationAI

Upgrade to Outline 1.7.0 or later, which contains the authorization fix (Vendor-released patch: v1.7.0; commit 1b91a295e10f58a1088c54f533773788325ff460). Self-hosted operators should pull the tagged v1.7.0 image/release and redeploy; consult GHSA-23jj-rp48-w7q7 for details. If you cannot patch immediately, reduce exposure by tightening who can obtain an authenticated account - disable open/public self-registration and restrict signups to trusted SSO domains, since the attack requires only a low-privilege account (trade-off: blocks legitimate self-service onboarding). You can also monitor and rate-limit or audit calls to the shares.create endpoint and review recently created public shares for links pointing at documents outside the creator's collections, and disable public sharing entirely if the feature is non-essential (trade-off: removes legitimate external sharing). These are detective/limiting controls only - none fully closes the IDOR, so upgrading remains the real remediation.